Today I went to try my first spinervals workout on the trainer and realized my back tire was flat. I found the culprit immediately - a shard of glass I ran over when practicing clipping in and out on my 2 miler in the parking lots a few days ago. 
Well, fortunately, I had a flat tire needing changed right in the comfort of my living room. I pulled out the spare tube, the tire levers, a pump and my computer (so I could follow how-to videos). I first learned how to take the back tire off. Then I changed the tire. Should note that changing the tire took FOREVER. However, I know how to do it and won't EVER forget how now.
After all that, I wasn't about to let that stop me from my workout. And so far, the tire appears to be holding air. So, I'll consider it a victory!
200x Electra Townie 24D/Brooks B67